In a process referred to as “packaging”, the components of an integrated circuit (IC) are assembled into a package and the final packaged IC is tested to verify its functionality. During packaging, dies (i.e., integrated circuit chips cut from finished wafers) are often attached to a substrate or support structure, such as a printed circuit board, and encapsulated with a packaging material, such as epoxy or plastic. Dies may be assembled in different arrangements depending on the application and specification of a design, among other factors.
A flip chip, for example, is a type of assembly in which dies are mounted to a flexible circuit board that is folded or “flipped” to form a three-dimensional package. Some flip chip assemblies have solder bumps on an active surface that provide electrical connection to a circuit board when the chip is turned upside down. Flip chips then normally undergo an encapsulation process which covers the surface of the chip with a protective material. A flip chip package, like other kinds of IC packages, typically includes input pins for receiving external signals and output pins for transmitting signals generated by the IC.